Manuel Zelaya (r) has been garnering international support since his exile
Ousted Honduran President Manuel Zelaya is to address the United Nations, as pressure builds from the international community for him to be reinstated.
Mr Zelaya's expulsion by the army on Sunday has been criticised in Brussels, Washington and Latin America as a coup.
He says he will return to Honduras on Thursday, accompanied by the head of the Organization of American States.
The OAS is to hold an emergency meeting on Tuesday to discuss whether to expel Honduras from the grouping.
Mr Zelaya is due to address the UN in New York on Tuesday, as he seeks to build upon growing international support.
His visit follows emergency talks by the world body on Monday evening.
Mr Zelaya, 57, was ousted amid stiff opposition from the courts, military, Congress and even some members of his own party to his plans to amend the constitution.
He had wanted to hold a non-binding referendum on the proposal, which critics say could have paved the way for Mr Zelaya - elected in 2006 and restricted to only one term - to run for re-election.
Supporters of the exiled leader have been clashing with security forces
Polls had been due to open on Sunday, but instead troops stormed the presidential palace at dawn, bundled the president to an airbase and flew him to Costa Rica.
The BBC's Stephen Gibbs, in the Honduran capital, Tegucigalpa, says Mr Zelaya, whose popularity in Honduras had been plummeting in recent months, has garnered impressive support since his exile.
A number of countries in the region have withdrawn ambassadors from Honduras.
Spain, the former colonial ruler of Honduras, has called on other EU countries to withdraw their ambassadors - Foreign Minister Miguel Angel Moratinos said member states had "not ruled out" the option.
Meanwhile, World Bank president Robert Zoellick said the bank had "put a pause" on its lending to Honduras.
Mr Zoellick said the bank was "working closely with the OAS and looking to the OAS to deal with its handling of the crisis under its democratic charter".
Our correspondent notes that even US President Barack Obama and his Venezuelan counterpart Hugo Chavez have found themselves in rare agreement over the issue - with both declaring that his expulsion was illegal.
The authorities in Honduras have been restricting broadcasts by media outlets perceived to be pro-Zelaya and protesters have been taunting soldiers that they have replaced the news with cartoons, our correspondent adds.
Addressing a late-night meeting on Monday of leaders from the OAS in Nicaragua, Mr Zelaya announced his plans to return.
"I want the support of whoever thinks I have the right to finish my presidency," said the deposed president, who was due to leave office next January.
He would accept an offer by OAS Secretary General Jose Miguel Insulza to accompany him back to Honduras on Thursday, he said.
It is unclear how Honduras's current leaders will react but they have previously said that Mr Zelaya would be jailed if he set foot in the country.
The replacement government has denied that any coup has taken place, saying that the Supreme Court had ordered the army to remove Mr Zelaya for acting unconstitutionally.
Congress immediately named an interim president, the assembly speaker, Roberto Micheletti, who has said an election will be held in November.
But over the past two days, hundreds of pro-Zelaya demonstrators have clashed with members of the security forces, demanding that the ousted leader be reinstated.
Honduran trade unions have also called for a general strike to protest against Mr Zelaya's removal.